Michael Holzheu [Fri, 11 Sep 2009 08:29:02 +0000 (10:29 +0200)]
[S390] tape: Fix device online messages
Currently, when a tape device is set online and no cartridge is loaded, we
get the messages "The tape cartridge has been successfully unloaded" and
"Determining the size of the recorded area". These messages are not correct.
To fix this, we now print the "cartridge loaded/unloaded" messages only,
when the load/unload event really occurs. In addition to that, the message
"Determining the size of the recorded area" is only printed, if a cartridge
is loaded.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
"lockdep: Fix backtraces" reveales a bug in early setup code: when
lockdep tries to save a stack backtrace before setup_arch has been
called the lowcore pointer for the current thread info pointer isn't
initialized yet.
However our save stack backtrace code relies on it. If the pointer
isn't initialized the saved backtrace will have zero entries.
lockdep however relies (correctly) on the fact that that cannot
happen.
A write access to some random memory region is the result.
Fix this by initializing the thread info pointer early.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The page_table_lock is already acquired in __pmd_alloc (mm/memory.c) and
it tries to populate the pud/pgd with a new pmd allocated. If another
thread populates it before we get a chance, we free the pmd using
pmd_free().
On s390x, pmd_free(even pud_free ) is #defined to crst_table_free(),
which acquires the page_table_lock to protect the crst_table index updates.
Hence this ends up in a recursive locking of the page_table_lock.
The solution suggested by Dave Hansen is to use a new spin lock in the mmu
context to protect the access to the crst_list and the pgtable_list.
Reported-by: Suzuki Poulose <suzuki@in.ibm.com> Cc: Dave Hansen <dave@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Hendrik Brueckner [Fri, 11 Sep 2009 08:28:56 +0000 (10:28 +0200)]
[S390] kvm: use console_initcall() to initialize s390 virtio console
Use a console_initcall() to initialize the s390 virtio console and
clean up s390 console initialization in setup.c.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Tested-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Michael Holzheu [Fri, 11 Sep 2009 08:28:50 +0000 (10:28 +0200)]
[S390] xpram: Remove checksum validation for suspend/resume
Currently in the suspend process checksums for the XPRAM partitions are
created and stored. During the resume process it is checked,
if the checksums are still the same. If this is not the case, a kernel panic
is triggered. Unfortunately this prevents XPRAM from beeing used as suspend
device, because in this case after the checksum has been created, the
memory image is written to XPRAM and therefore the contents of the suspend
partition is changed. In order to allow XPRAM to be used as suspend device,
this patch removes the checksum validation.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Michael Holzheu [Fri, 11 Sep 2009 08:28:49 +0000 (10:28 +0200)]
[S390] vmur: Invalid allocation sequence for vmur class
The vmur class is allocated after the CCW driver is registered
and it is destroyed before the CCW driver is unregistered.
This is not the correct sequence, because the vmur class can be used
via driver core callbacks that are triggered during the CCW driver
deregistration. For Example:
1. vmur device is online
2. vmur module is unloaded
[S390] kernel: always keep machine flags in lowcore
Eleminate the local variable machine_flags and always change machine
flags directly in the lowcore.
This avoids confusion about when and why the two variables have to be
synchronized.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Nelson Elhage [Fri, 11 Sep 2009 08:28:44 +0000 (10:28 +0200)]
[S390] clean up linker script using new linker script macros.
Note that this patch moves .data.init_task inside _edata. In
addition, the alignment of .init.ramfs changes: It is now PAGE_ALIGNED
and __initramfs_end is arbitrarily aligned; Previously it was
only aligned to a 0x100-byte boundary, and always ended on an even
byte.
This change results in fewer output sections and in some data being
reordered, but should have no functional effect.
Signed-off-by: Nelson Elhage <nelhage@ksplice.com> Signed-off-by: Tim Abbott <tabbott@ksplice.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux-s390@vger.kernel.org Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Tim Abbott [Fri, 11 Sep 2009 08:28:43 +0000 (10:28 +0200)]
[S390] Use macros for .data.page_aligned.
.data.page_aligned should not need a separate output section, so as
part of this cleanup I moved into the .data output section in the
linker scripts in order to eliminate unnecessary references to the
section name.
Remove the reference to .data.idt, since nothing is put into the
.data.idt section on the s390 architecture. It looks like Cyrill
Gorcunov posted a patch to remove the .data.idt code on s390
previously:
CCing him and the people who acked that patch in case there's a reason
it wasn't applied.
Signed-off-by: Tim Abbott <tabbott@ksplice.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Acked-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Hendrik Brueckner [Fri, 11 Sep 2009 08:28:42 +0000 (10:28 +0200)]
[S390] move (io|sysc)_restore_trace_psw into .data section
The sysc_restore_trace_psw and io_restore_trace_psw storage locations
are created in the .text section. When creating and IPLing from a named
saved system (NSS), writing to these locations causes a protection exception
(because the .text section is mapped as shared read-only in the NSS).
To permit write access, move the storage locations into the .data section.
Hendrik Brueckner [Fri, 11 Sep 2009 08:28:40 +0000 (10:28 +0200)]
[S390] kernel: Append scpdata to kernel boot command line
Append scpdata to the kernel boot command line. If scpdata starts
with the equal sign (=), the kernel boot command line is replaced.
(For consistency with zIPL and IPL PARM parameters.)
To use scpdata for the kernel boot command line, scpdata must consist
of ascii characters only. If scpdata contains other characters,
scpdata is not appended to the kernel boot command line.
In addition, re-IPL is extended for setting scpdata for the next
Linux reboot.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Frank Munzert [Fri, 11 Sep 2009 08:28:39 +0000 (10:28 +0200)]
[S390] tape: use init_timer_on_stack() rather than init_timer()
With CONFIG_DEBUG_OBJECTS_TIMERS=y "chccwdev --online" for a tape device
will fail with message "ODEBUG: object is on stack, but not annotated".
We now use init_timer_on_stack.
Signed-off-by: Frank Munzert <munzert@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Introduce get_clock_monotonic() function which can be used to get a
(fast) timestamp. Resolution is the same as for get_clock(). The
only difference is that the timestamps are monotonic and don't jump
backward or forward.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Stefan Haberland [Fri, 11 Sep 2009 08:28:30 +0000 (10:28 +0200)]
[S390] dasd: fix message naming
This patch fixes message naming so that generic dasd messages do not
contain the device discipline. For this purpose the dev_ makros are
replaced by pr_ makros for generic dasd messages.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Sebastian Ott [Fri, 11 Sep 2009 08:28:27 +0000 (10:28 +0200)]
[S390] cio: remove ccw_device init_name
We used the init_name to set the console ccw_device's name early
at the boot stage. This patch moves the name setting (for all ccw
devices) to the point where we actually register the device. At this
time we can do dynamic allocations and therefore use dev_set_name.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Sebastian Ott [Fri, 11 Sep 2009 08:28:26 +0000 (10:28 +0200)]
[S390] cio: move final put_device to ccw_device_unregister
We use a test_and_clear_bit to prevent a device from being
unregistered twice. Unfortunately in this cases the "final"
put_device (from device_initialize) was issued more than once,
resulting in an use after free error. Fix this by moving this
put_device to ccw_device_unregister.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Sebastian Ott [Fri, 11 Sep 2009 08:28:25 +0000 (10:28 +0200)]
[S390] cio: remove subchannel init_name
We used the init_name to set the console subchannels name early
at the boot stage. With the patch cio: fix memleak in subchannel validation
we moved the name setting to the point where we actually register the
console subchannel. At this time we can do dynamic allocations and therefore
use dev_set_name.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Sebastian Ott [Fri, 11 Sep 2009 08:28:24 +0000 (10:28 +0200)]
[S390] cio: fix memleak in subchannel validation
When scanning for new subchannels we have a code path where we allocate
memory for a struct subchannel, set the device name (which is dynamically
allocated now) and do a check if the underlying device is blacklisted - if
so we free the subchannel structure.
Since we have not set up refcounting at this stage, the device name's memory
is lost. Fix this by moving the dev_set_name after the blacklist test.
Note: With this patch the init_name for the console subchannel becomes
virtually obsolete.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Sebastian Ott [Fri, 11 Sep 2009 08:28:23 +0000 (10:28 +0200)]
[S390] cio: fix use after free in s390 debug feature
When using s390dbf with "%s" in sprintf format strings the string itself
is not copied to the dbf buffer.
Since in this case only pointers are stored in the s390dbf, we should
not use dev_name - which is bound to the lifetime of the device.
Reading this entry from s390dbf after the device was released will cause
an use after free error.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Michael Ernst [Fri, 11 Sep 2009 08:28:21 +0000 (10:28 +0200)]
[S390] cio: failing set online/offline processing.
When unit checks trigger sensing the device state is set to W4SENSE
until sense completion; then the device state is set back to
ONLINE. If a unit check occurs while set online or set offline
requests are processed then it might happen that the device's
temporary W4SENSE state causes these functions to terminate,
leaving the device in an inconsistent state when the state is set
back to ONLINE later on so that the device cannot be set online or
offline any longer.
To solve this, set online/offline and related rollback or error
routines are processed only if the device is in a final or
DISCONNECTED state.
Signed-off-by: Michael Ernst <mernst@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Sebastian Ott [Fri, 11 Sep 2009 08:28:20 +0000 (10:28 +0200)]
[S390] cio: ensure to hold a reference for deferred deregistration
Ensure to always hold an extra device reference for scheduling a
subchannel deregistration, by moving the get_device to
ccw_device_schedule_sch_unregister. This fixes an use after free
error in ccw_device_call_sch_unregister where put_device was called
on an already freed device structure.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Sebastian Ott [Fri, 11 Sep 2009 08:28:17 +0000 (10:28 +0200)]
[S390] cio: fix not oper handling after failed [on|off]line processing
If online/offline processing of a ccw device fails, resulting in not
operational state, notify the driver and unregister the device in case
the driver dosn't want to keep it.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
[S390] cio: move scsw helper functions to header file
All scsw helper functions are very short and usage of them shouldn't
result in function calls. Therefore we move them to a separate header
file.
Also saves a lot of EXPORT_SYMBOLs.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Peter Oberparleiter [Fri, 11 Sep 2009 08:28:14 +0000 (10:28 +0200)]
[S390] cio: fix ineffective verify event
Path verification events occurring for offline devices are currently
ignored. As a result, offline devices are not removed, even though
they might no longer be accessible (for example because the last path
to the device was varied offline). Fix this by scheduling a status
evaluation for the affected subchannel when a path verification event
occurs.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Commit b8313b6da7e2e7c7f47d93d8561969a3ff9ba0ea ("dm log: remove incorrect
field from userspace table output") added a call to strstr() with a
single-character "needle" string parameter.
Unfortunately some versions of gcc replace such calls to strstr() by calls
to strchr() behind our back. This causes linking errors if strchr() is
defined as an inline function in <asm/string.h> (e.g. on m68k):
* lookup-permissions-cleanup:
jffs2/jfs/xfs: switch over to 'check_acl' rather than 'permission()'
ext[234]: move over to 'check_acl' permission model
shmfs: use 'check_acl' instead of 'permission'
Make 'check_acl()' a first-class filesystem op
Simplify exec_permission_lite(), part 3
Simplify exec_permission_lite() further
Simplify exec_permission_lite() logic
Do not call 'ima_path_check()' for each path component
After applying the patch:
$ ./hello
Trace trap # user-mode execution after execve() finishes
If the ELF headers are actually self-inconsistent, then dying is fine.
But having no PROT_WRITE segment is perfectly normal and correct if
there is no segment with p_memsz > p_filesz (i.e. bss). John Reiser
suggested checking for PROT_WRITE in the bss logic. I think it makes
most sense to simply apply the bss logic only when there is bss.
This patch looks less trivial than it is due to some reindentation.
It just moves the "if (last_bss > elf_bss) {" test up to include the
partial-page bss logic as well as the more-pages bss logic.
Reported-by: John Reiser <jreiser@bitwagon.com> Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
"This seems to generate /sys/block/$device/queue and its contents for
everyone who is using queues, not just for those queues that have a
non-NULL queue->request_fn."
Note that embedding a queue inside another object has always been
an illegal construct, since the queues are reference counted and
must persist until the last reference is dropped. So aoe was
always buggy in this respect (Jens).
Signed-off-by: Ed Cashin <ecashin@coraid.com> Cc: Andy Whitcroft <apw@canonical.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Bruno Premont <bonbons@linux-vserver.org> Cc: Martin K. Petersen <martin.petersen@oracle.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
i915: disable interrupts before tearing down GEM state
Reinette Chatre reports a frozen system (with blinking keyboard LEDs)
when switching from graphics mode to the text console, or when
suspending (which does the same thing). With netconsole, the oops
turned out to be
BUG: unable to handle kernel NULL pointer dereference at 0000000000000084
IP: [<ffffffffa03ecaab>] i915_driver_irq_handler+0x26b/0xd20 [i915]
and it's due to the i915_gem.c code doing drm_irq_uninstall() after
having done i915_gem_idle(). And the i915_gem_idle() path will do
but if an i915 interrupt comes in after this stage, it may want to
access that hw_status_page, and gets the above NULL pointer dereference.
And since the NULL pointer dereference happens from within an interrupt,
and with the screen still in graphics mode, the common end result is
simply a silently hung machine.
Fix it by simply uninstalling the irq handler before idling rather than
after. Fixes
Linus Torvalds [Fri, 28 Aug 2009 19:12:24 +0000 (12:12 -0700)]
ext[234]: move over to 'check_acl' permission model
Don't implement per-filesystem 'extX_permission()' functions that have
to be called for every path component operation, and instead just expose
the actual ACL checking so that the VFS layer can now do it for us.
Linus Torvalds [Fri, 28 Aug 2009 19:04:28 +0000 (12:04 -0700)]
shmfs: use 'check_acl' instead of 'permission'
shmfs wants purely standard POSIX ACL semantics, so we can use the new
generic VFS layer POSIX ACL checking rather than cooking our own
'permission()' function.
Linus Torvalds [Fri, 28 Aug 2009 18:51:25 +0000 (11:51 -0700)]
Make 'check_acl()' a first-class filesystem op
This is stage one in flattening out the callchains for the common
permission testing. Rather than have most filesystem implement their
own inode->i_op->permission function that just calls back down to the
VFS layers 'generic_permission()' with the per-filesystem ACL checking
function, the filesystem can just expose its 'check_acl' function
directly, and let the VFS layer do everything for it.
This is all just preparatory - no filesystem actually enables this yet.
Linus Torvalds [Fri, 28 Aug 2009 18:08:31 +0000 (11:08 -0700)]
Simplify exec_permission_lite(), part 3
Don't call down to the generic inode_permission() function just to
call the inode-specific permission function - just do it directly.
The generic inode_permission() code does things like checking MAY_WRITE
and devcgroup_inode_permission(), neither of which are relevant for the
light pathname walk permission checks (we always do just MAY_EXEC, and
the inode is never a special device).
Linus Torvalds [Fri, 28 Aug 2009 17:53:56 +0000 (10:53 -0700)]
Simplify exec_permission_lite() further
This function is only called for path components that are already known
to be directories (they have a '->lookup' method). So don't bother
doing that whole S_ISDIR() testing, the whole point of the 'lite()'
version is that we know that we are looking at a directory component,
and that we're only checking name lookup permission.
Zhenyu Wang [Tue, 8 Sep 2009 06:52:25 +0000 (14:52 +0800)]
drm/i915: fix mask bits setting
eDP is exclusive connector too, and add missing crtc_mask
setting for TV.
This fixes
http://bugzilla.kernel.org/show_bug.cgi?id=14139
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com> Reported-and-tested-by: Carlos R. Mafra <crmafra2@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel:
agp/intel: support for new chip variant of IGDNG mobile
drm/i915: Unref old_obj on get_fence_reg() error path
drm/i915: increase default latency constant (v2 w/comment)
Dave Airlie [Mon, 7 Sep 2009 05:26:19 +0000 (15:26 +1000)]
drm/radeon/kms: add LTE/GTE discard + rv515 two sided stencil register.
This adds some rv350+ register for LTE/GTE discard,
and enables the rv515 two sided stencil register.
It also disables the DEPTHXY_OFFSET register which
can be used to workaround the CS checker.
Moves rs690 to proper place in rs600 and uses correct
table on rs600.
breaks the build of the gianfar driver because "dev" is undefined in
this function. To quickly test rc9 I changed this to priv->ndev but I do
not know if this is the correct one.
--------------------
Signed-off-by: David S. Miller <davem@davemloft.net>
powerpc: Fix i8259 interrupt driver kernel crash on ML510
This patch fixes a null pointer exception caused by removal of
'ack()' for level interrupts in the Xilinx interrupt driver. A recent
change to the xilinx interrupt controller removed the ack hook for
level irqs.
Signed-off-by: Roderick Colenbrander <thunderbird2k@gmail.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm:
dm snapshot: fix on disk chunk size validation
dm exception store: split set_chunk_size
dm snapshot: fix header corruption race on invalidation
dm snapshot: refactor zero_disk_area to use chunk_io
dm log: userspace add luid to distinguish between concurrent log instances
dm raid1: do not allow log_failure variable to unset after being set
dm log: remove incorrect field from userspace table output
dm log: fix userspace status output
dm stripe: expose correct io hints
dm table: add more context to terse warning messages
dm table: fix queue_limit checking device iterator
dm snapshot: implement iterate devices
dm multipath: fix oops when request based io fails when no paths
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
sparc64: Fix bootup with mcount in some configs.
sparc64: Kill spurious NMI watchdog triggers by increasing limit to 30 seconds.
Nicolas Pitre [Sat, 5 Sep 2009 04:25:37 +0000 (00:25 -0400)]
ext2: fix unbalanced kmap()/kunmap()
In ext2_rename(), dir_page is acquired through ext2_dotdot(). It is
then released through ext2_set_link() but only if old_dir != new_dir.
Failing that, the pkmap reference count is never decremented and the
page remains pinned forever. Repeat that a couple times with highmem
pages and all pkmap slots get exhausted, and every further kmap() calls
end up stalling on the pkmap_map_wait queue at which point the whole
system comes to a halt.
Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2:
ocfs2: ocfs2_write_begin_nolock() should handle len=0
ocfs2: invalidate dentry if its dentry_lock isn't initialized.
pty: don't limit the writes to 'pty_space()' inside 'pty_write()'
The whole write-room thing is something that is up to the _caller_ to
worry about, not the pty layer itself. The total buffer space will
still be limited by the buffering routines themselves, so there is no
advantage or need in having pty_write() artificially limit the size
somehow.
And what happened was that the caller (the n_tty line discipline, in
this case) may have verified that there is room for 2 bytes to be
written (for NL -> CRNL expansion), and it used to then do those writes
as two single-byte writes. And if the first byte written (CR) then
caused a new tty buffer to be allocated, pty_space() may have returned
zero when trying to write the second byte (LF), and then incorrectly
failed the write - leading to a lost newline character.
This should finally fix
http://bugzilla.kernel.org/show_bug.cgi?id=14015
Reported-by: Mikael Pettersson <mikpe@it.uu.se> Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When translating CR to CRNL in the n_tty line discipline, we did it as
two tty_put_char() calls. Which works, but is stupid, and has caused
problems before too with bad interactions with the write_room() logic.
The generic USB serial driver had that problem, for example.
Now the pty layer had similar issues after being moved to the generic
tty buffering code (in commit d945cb9cce20ac7143c2de8d88b187f62db99bdc:
"pty: Rework the pty layer to use the normal buffering logic").
So stop doing the silly separate two writes, and do it as a single write
instead. That's what the n_tty layer already does for the space
expansion of tabs (XTABS), and it means that we'll now always have just
a single write for the CRNL to match the single 'tty_write_room()' test,
which hopefully means that the next time somebody screws up buffering,
it won't cause weeks of debugging.
But the root of the problem lies in the fact that do_execve() path calls
tracehook_report_exec() which can stop if the tracer sets PT_TRACE_EXEC.
The tracee must not sleep in TASK_TRACED holding this mutex. Even if we
remove ->cred_guard_mutex from mm_for_maps() and proc_pid_attr_write(),
another task doing PTRACE_ATTACH should not hang until it is killed or the
tracee resumes.
With this patch do_execve() does not use ->cred_guard_mutex directly and
we do not hold it throughout, instead:
- introduce prepare_bprm_creds() helper, it locks the mutex
and calls prepare_exec_creds() to initialize bprm->cred.
- install_exec_creds() drops the mutex after commit_creds(),
and thus before tracehook_report_exec()->ptrace_stop().
or, if exec fails,
free_bprm() drops this mutex when bprm->cred != NULL which
indicates install_exec_creds() was not called.
Reported-by: Tom Horsley <tom.horsley@att.net> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: David Howells <dhowells@redhat.com> Cc: Roland McGrath <roland@redhat.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
page-allocator: always change pageblock ownership when anti-fragmentation is disabled
On low-memory systems, anti-fragmentation gets disabled as fragmentation
cannot be avoided on a sufficiently large boundary to be worthwhile. Once
disabled, there is a period of time when all the pageblocks are marked
MOVABLE and the expectation is that they get marked UNMOVABLE at each call
to __rmqueue_fallback().
However, when MAX_ORDER is large the pageblocks do not change ownership
because the normal criteria are not met. This has the effect of
prematurely breaking up too many large contiguous blocks. This is most
serious on NOMMU systems which depend on high-order allocations to boot.
This patch causes pageblocks to change ownership on every fallback when
anti-fragmentation is disabled. This prevents the large blocks being
prematurely broken up.
This is a fix to commit 49255c619fbd482d704289b5eb2795f8e3b7ff2e [page
allocator: move check for disabled anti-fragmentation out of fastpath] and
the problem affects 2.6.31-rc8.
Signed-off-by: Mel Gorman <mel@csn.ul.ie> Tested-by: Paul Mundt <lethal@linux-sh.org> Cc: David Howells <dhowells@redhat.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Greg Ungerer <gerg@snapgear.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Howells [Sat, 5 Sep 2009 18:17:07 +0000 (11:17 -0700)]
nommu: fix error handling in do_mmap_pgoff()
Fix the error handling in do_mmap_pgoff(). If do_mmap_shared_file() or
do_mmap_private() fail, we jump to the error_put_region label at which
point we cann __put_nommu_region() on the region - but we haven't yet
added the region to the tree, and so __put_nommu_region() may BUG
because the region tree is empty or it may corrupt the region tree.
To get around this, we can afford to add the region to the region tree
before calling do_mmap_shared_file() or do_mmap_private() as we keep
nommu_region_sem write-locked, so no-one can race with us by seeing a
transient region.
Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Paul Mundt <lethal@linux-sh.org> Cc: Mel Gorman <mel@csn.ul.ie> Acked-by: Greg Ungerer <gerg@snapgear.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
cancel_delayed_work() has to use del_timer_sync() to guarantee the timer
function is not running after return. But most users doesn't actually
need this, and del_timer_sync() has problems: it is not useable from
interrupt, and it depends on every lock which could be taken from irq.
Introduce __cancel_delayed_work() which calls del_timer() instead.
The immediate reason for this patch is
http://bugzilla.kernel.org/show_bug.cgi?id=13757
but hopefully this helper makes sense anyway.
As for 13757 bug, actually we need requeue_delayed_work(), but its
semantics are not yet clear.
Merge this patch early to resolves cross-tree interdependencies between
input and infiniband.
Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Roland Dreier <rdreier@cisco.com> Cc: Stefan Richter <stefanr@s5r6.in-berlin.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
projects / users / hch / uuid.git / log